Cultivation method for promoting growth and development of aerial roots of densely-planted summer corn

Abstract

The invention belongs to the field of crop planting, and particularly relates to a cultivation method for promoting growth and development of aerial roots of densely-planted summer corn. According to the method, the growth and development effect of the aerial roots of the densely-planted summer corn is induced by combining the plant spacing optimization, the improvement of the physicochemical characteristics of farmland plough layer soil, the chemical control in a key period, the fertilization strategy of front-nitrogen and rear-nitrogen movement and the like. Experiments prove that by means of the cultivation method, the number of layers of aerial roots, the number of aerial roots entering soil, the diameter of the aerial roots, the substance accumulation amount of the aerial roots, the lodging rate of plant roots, the yield and other indexes are all obviously improved. The cultivation method provided by the invention has an obvious promotion effect on inducing growth and development of aerial roots of the rational close-planting corn, so that the lodging-resistant capability of the close-planting corn is enhanced, absorption and utilization of plants to water and nutrients are facilitated, and yield increase is realized.

Description

Technical Field

[0001] The invention belongs to the field of crop planting, and in particular relates to a cultivation method for promoting the growth and development of aerial roots of densely planted summer corn. Background Art

[0002] The root system is an important part of the plant that combines with the soil and fixes the entire plant. It plays a vital role in the absorption of nutrients and water by the plant and the stability of the plant. Corn is a fibrous root crop, which is composed of radicle and nodal roots, and can be divided into primary roots, secondary roots and aerial roots. Aerial roots are commonly known as "overlord roots", which refer to the roots exposed above the air surface layer and belong to the auxiliary root system with a supporting function. Corn aerial roots are an important part of the corn root system. Developed aerial roots can not only fix the plant and improve the plant's drought resistance and lodging resistance, but also absorb more water and nutrients for plant growth and development. Reasonable increase in planting density has become an important way to increase corn yields at present and in the future, but lodging caused by dense planting is still a common problem in current corn production, which seriously restricts the potential of dense planting to increase corn yield. The poor development of the root system, mainly corn aerial roots, is one of the important reasons for the easy lodging of densely planted corn. The occurrence and development of corn aerial roots are not only related to the genetic factors of the variety, but also the farmland cultivation and management measures are also important factors affecting the development of corn aerial roots. Therefore, developing a cultivation method that can promote the growth and development of aerial roots of densely planted corn can not only improve the lodging resistance of densely planted corn plants, but also help enhance the plant's absorption of soil nutrients and water, which is of great significance for achieving high-yield potential of densely planted corn.

[0003] In the field cultivation and production of corn, the existing technologies for regulating the development of corn aerial roots are mostly through spraying chemical control agents at critical periods to prevent excessive growth of plants and promote the growth and development of aerial roots. However, the growth and development of aerial roots are also closely related to factors such as the field environment and soil conditions. Existing technologies often ignore the concept of combining chemical control technology with other key regulatory measures in farmland cultivation management. The use of chemical control agents alone without paying attention to other field cultivation management often does not achieve good results in promoting the growth and development of aerial roots.

[0004] Therefore, based on this, the technical solution of the present invention is proposed. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention provides a cultivation method for promoting the growth and development of aerial roots of densely planted summer corn, which achieves the effect of inducing the growth and development of aerial roots of densely planted summer corn by combining optimization of plant and row spacing, improvement of physical and chemical properties of farmland topsoil, chemical control during critical periods, and a fertilization strategy of nitrogen application in the front and back.

[0006] The solution of the present invention is to provide a cultivation method for promoting the growth and development of aerial roots of densely planted summer corn, and the cultivation method comprises the following steps:

[0007] (1) Before sowing winter wheat, the previous crop of summer corn, the corn stalks after autumn harvest are crushed and returned to the field, followed by deep tillage and rotary tillage;

[0008] (2) After the winter wheat crop is harvested, the straw is crushed and returned to the field, and then summer corn is sown and basal fertilizer and water are applied;

[0009] (3) When summer corn is in its 6-leaf stage, combine tillage and loosening the soil to cultivate the soil, and then apply water and fertilizer;

[0010] (4) Apply benzylamine and ethephon water solution during the 9-leaf stage of summer corn;

[0011] (5) Apply nitrogen fertilizer when summer corn has 12 leaves;

[0012] (6) During the period from jointing stage to flowering and silking stage of summer corn, ensure that the water holding capacity of field soil is maintained between 65% and 70%;

[0013] (7) The conventional field pest and weed control methods for summer corn throughout the entire growth period are carried out in the same way as those for ordinary high-yield fields.

[0014] More specifically, the cultivation method of the present invention is:

[0015] (S1) Before sowing winter wheat, the previous crop of summer corn, the corn stalks after autumn harvest are crushed and returned to the field by a stubble destroyer, and the tillage layer is deep-plowed once with an agricultural deep tiller to a depth of 35 to 40 cm, followed by conventional rotary tillage twice to a depth of 15 to 20 cm to achieve a thick and fertile tillage layer. (Note: The planting system in the Huanghuaihai Plain is mainly a winter wheat-summer corn double-cropping system)

[0016] (S2) After the previous wheat crop was harvested, the straw was crushed and returned to the field. The summer corn was fertilized and sown using a sowing and fertilization machine. The sowing method adopted wide and narrow row staggered planting, with a wide row of 80 cm and a narrow row of 40 cm. The planting density was 5000-5500 plants / mu, and the plant spacing was 20-22 cm. The plant row staggered planting method was as follows: Figure 1 As shown. Base fertilizer is 9.8kg / mu of urea containing 46% N, 12kg / mu of superphosphate containing 46% P2O5, and 11kg / mu of potassium chloride containing 60% K2O. Among them, phosphate fertilizer and potassium fertilizer are all applied once as base fertilizer, and nitrogen fertilizer application includes base application and topdressing. The base application of nitrogen fertilizer is 30% of the total nitrogen application. After corn is sown, about 30 cubic meters of water is applied per mu of land through flooding. It is not advisable to irrigate too much water, just enough to meet the corn germination.

[0017] (S3) During the 6-leaf development period of summer corn, the soil is cultivated in combination with inter-row tillage to loosen the soil. The soil between the corn rows is cultivated at the root, and the height of the cultivation is about 5 cm to form a soil ridge to increase the light-receiving area of ​​the topsoil. After the cultivation, a micro-spraying belt is laid in the middle of each wide row, and 9.8 kg / mu of urea containing 46% N (30% of the total nitrogen application) and 2.5 kg of organic water-soluble fertilizer containing mineral potassium humate are diluted to about 200 kg, and then applied to the soil through integrated water and fertilizer sprinkler irrigation, spraying about 25 cubic meters of water.

[0018] (S4) When summer corn has 9 leaves, choose a sunny day after 4 p.m. and use 30 mL of 30% benzylamine·ethephon water per mu, add 25 kg of water and spray evenly using a drone to prevent the internodes at the base of the stem from growing too fast and facilitate the development of aerial roots.

[0019] (S5) When summer corn has 12 leaves, 13.1 kg / mu of urea containing 46% nitrogen (40% of the total nitrogen application) is evenly sprayed on the soil through micro-spraying and fertilizer integration, with about 25 to 30 cubic meters of water sprayed.

[0020] (S6) During the period from the jointing stage to the flowering and silking stage of corn, in order to maintain a reasonable humidity environment in the field, it is necessary to ensure that the water holding capacity of the field soil is maintained between 65% and 70%. If the water holding capacity of the field soil is lower than 65%, micro-sprinkler irrigation should be used in time to avoid soil drought and water shortage that affects the development and burial of aerial roots.

[0021] (S7) Conventional methods for controlling diseases, insect pests and weeds in the field during the entire growth period of corn are carried out in the same way as those in ordinary high-yield fields.

[0022] The beneficial effects of the present invention are:

[0023] The cultivation method of the present invention integrates technologies such as thick fertile arable soil, staggered planting of corn plants in wide and narrow rows, intertillage and soil cultivation, front-nitrogen and back-shift application technology based on micro-sprinkler irrigation, chemical control during the critical period, and optimized control of field soil water holding capacity before corn flowering. It is not only conducive to promoting the growth and development of aerial roots of densely planted summer corn, but also can improve the utilization efficiency and yield of farmland corn resources by improving the quality of arable soil and optimizing nitrogen fertilizer application, which is conducive to green and sustainable agricultural production. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1This is a staggered planting pattern diagram of plants based on wide and narrow rows. DETAILED DESCRIPTION

[0026] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0027] Example 1 and Comparative Example 1

[0028] In 2017, corn varieties Lianchuang 808 and Keyu 186 were used as test materials. Experiments were carried out at the Luancheng Agricultural Ecosystem Experimental Station of Shijiazhuang City, Hebei Province, Chinese Academy of Sciences. A total of two different cultivation and planting patterns were set up, cultivation and planting pattern 1 (T1), that is, the control pattern (comparative example 1), which is the common planting pattern of local farmers; cultivation and planting pattern 2 (T2), that is, the cultivation pattern of the present invention (Example 1).

[0029] The cultivation method provided in Example 1 is:

[0030] (1) Before sowing the previous wheat crop, that is, before sowing wheat in autumn 2016, the previous corn stalks were crushed and returned to the field, and then the field was deep plowed once with an agricultural deep plowing machine to a depth of 35 to 40 cm, followed by two rotary tillage operations.

[0031] (2) After wheat harvest, the stubble was removed and a special integrated sowing and fertilizing machine was used for fertilization and sowing. The sowing method adopted wide and narrow row staggered planting, with a wide row of 80 cm and a narrow row of 40 cm. The planting density was 5,000 plants. The base fertilizer was 9.8 kg / mu of urea containing 46% N, 12 kg / mu of superphosphate containing 46% P2O5, and 11 kg / mu of potassium chloride containing 60% K2O. Among them, phosphorus fertilizer and potassium fertilizer were all applied as a one-time base fertilizer, and nitrogen fertilizer application included base application and topdressing, with the base application of nitrogen fertilizer accounting for 30% of the total nitrogen application. After corn was sown, about 30 cubic meters of water was applied per mu of land for seedling emergence through flooding.

[0032] (3) During the six-leaf development period of summer corn, the soil is cultivated and loosened by inter-row cultivation. The soil between the corn rows is cultivated to the root, and the height of the cultivation is about 5 cm. After the cultivation, the micro-spraying tape is laid in the middle of each wide row, and 9.8 kg / mu of urea with a nitrogen content of 46% (30% of the total nitrogen application) and 2.5 kg of organic water-soluble fertilizer containing mineral potassium humate are diluted to about 200 kg, and sprayed on the soil through water-fertilizer integration, spraying about 25 cubic meters of water.

[0033] (4) When summer corn is in its 9-leaf stage, choose a sunny day after 4 p.m. and use 30 mL of 30% benzylamine-ethephon water per mu, dilute with 25 kg of water and use a drone to spray evenly.

[0034] (5) When summer corn leaves are 12 leaves in development, 13.1 kg / mu of urea containing 46% nitrogen (40% of the total nitrogen application) is evenly sprayed on the soil through micro-spraying and fertilizer integration, with about 25 to 30 cubic meters of water sprayed.

[0035] (6) During the period from the jointing stage to the flowering and silking stage of summer corn, in order to maintain a reasonable humidity environment in the field, the water holding capacity of the field soil must be ensured to be between 65% and 70%. If the water holding capacity of the field soil is lower than 65%, micro-sprinkler irrigation should be used in a timely manner to avoid soil drought and water shortage that affects the development and burial of aerial roots.

[0036] (7) Conventional field pest and weed control methods during the entire growth period are the same as those for conventional fields.

[0037] The cultivation method provided in Comparative Example 1 is:

[0038] No deep tillage treatment was performed on the farmland before sowing. After the previous crop of wheat was harvested, a fertilizer-seeding machine was used for conventional fertilization and sowing with equal row spacing. The fertilizer applied was a conventional compound fertilizer for corn (the total nutrient content of the compound fertilizer was ≥40%, and the contents of N, P2O5, and K2O were 27%, 6%, and 7%, respectively). The amount per mu was 50 kg, all applied as a one-time basal fertilizer, without any topdressing, and the planting density was 5,000 plants / mu. After corn was sown, about 40 cubic meters of water was poured for seedling emergence. During the growth period of corn, except for flooding and watering in case of drought, prevention and control of pests and diseases, and chemical control, no other field cultivation and management measures were arranged.

[0039] The parameters of aerial root traits of corn under different cultivation modes were investigated at the physiological maturity stage, including the number of layers of aerial roots, the number of aerial roots entering the soil, the diameter of aerial roots, the dry matter accumulation of aerial roots in the aboveground part, and the root lodging rate and yield of the plants, as shown in Table 1.

[0040] Table 1 Effects of different planting patterns on maize aerial root characteristics, plant root lodging rate and yield in 2017

[0041]

[0042] As shown in Table 1, compared with the conventional cultivation and planting mode 1 (T1), the cultivation and planting mode 2 (T2) of the present invention significantly increased the number of layers of aerial roots, the number of aerial roots in the soil, the diameter of aerial roots, and the amount of material accumulation of aerial roots of the participating corn varieties Lianchuang 808 and Keyu 186. The increases of the two varieties were 10.5%, 18.4%, 19.5%, 21.4% and 21.1%, 12.3%, 11.6%, 19.5%, respectively. Compared with T1, T2 significantly reduced the lodging rate of plant roots and increased grain yield. The root lodging rate of the two varieties under the T2 cultivation and planting mode was reduced by 71.4% and 64.5% respectively compared with T1, and the grain yield increased by 8.3% and 7.0%, respectively. The data results show that the cultivation and planting mode 2 of the present invention can significantly promote the growth and development of corn aerial roots, thereby reducing the lodging rate of plant roots and increasing grain yield.

[0043] Example 2 and Comparative Example 2

[0044] In 2018, corn variety Keyu 186 was used as the test material, and experiments were carried out at Kangzhuang Farm in Xinhua District, Shijiazhuang City, Hebei Province. Two different cultivation and planting modes were set up, namely, cultivation and planting mode 1 (T1), i.e., the control mode (Comparative Example 2), which is the common planting mode of local farmers; and cultivation and planting mode 2 (T2), i.e., the cultivation mode of the present invention (Example 2). The corn cultivation and management steps of cultivation and planting mode 1 and cultivation and planting mode 2 in 2018 refer to Comparative Example 1 and Example 1.

[0045] During the physiological maturity period, the parameters of aerial root traits in different cultivation modes were investigated, including the number of layers of aerial roots, the number of aerial roots entering the soil, the diameter of aerial roots, the dry matter accumulation of aerial roots in the aboveground part, as well as the root lodging rate and yield of the plants, as shown in Table 2 below.

[0046] Table 2 Effects of different cultivation patterns on maize aerial root characteristics, plant root lodging rate and yield in 2018

[0047] Cultivation pattern T1 T2 Aerial root layer number 2.1 2.5 Number of aerial roots in soil 22.0 25.4 Aerial root diameter (mm) 3.4 3.8 Aerial root material accumulation (g / plant) 17.0 20.8 Plant root lodging rate (%) 6.9 2.6 Yield (kg / mu) 600.8 628.6

[0048] As shown in Table 2, the test results in 2018 showed that compared with the cultivation mode 1 (T1), the cultivation mode 2 (T2) of the present invention increased the number of layers of aerial roots, the number of aerial roots in the soil, the diameter of aerial roots, and the accumulation of aerial root substances by 17.6%, 15.3%, 10.7%, and 22.2%, respectively. The root lodging rate of plants treated with T2 was 62.3% lower than that of T1, and the grain yield of T2 was 4.6% higher than that of T1.

[0049] In summary, the cultivation method described in the present invention has an obvious promoting effect on inducing the growth and development of aerial roots of reasonably densely planted corn, which not only enhances the lodging resistance of densely planted corn, but also is beneficial to the plant's absorption and utilization of water and nutrients and achieves increased yield.

[0050] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A cultivation method for promoting the growth and development of aerial roots of densely planted summer corn, characterized in that: The cultivation method comprises the following steps: (1) Before sowing winter wheat, the previous crop of summer corn, the corn stalks after autumn harvest are crushed and returned to the field, followed by deep tillage and rotary tillage; (2) After the winter wheat crop is harvested, the straw is crushed and returned to the field, and then summer corn is sown and basal fertilizer and water are applied; (3) When summer corn is in its 6-leaf stage, combine tillage and loosening the soil to cultivate the soil, and then apply water and fertilizer; (4) Apply benzylamine and ethephon water solution during the 9-leaf stage of summer corn; (5) Apply nitrogen fertilizer when summer corn has 12 leaves; (6) During the period from jointing stage to flowering and silking stage of summer corn, ensure that the water holding capacity of field soil is maintained between 65% and 70%; (7) The conventional field pest and weed control methods for summer corn throughout the entire growth period are carried out in the same way as those for ordinary high-yield fields.

2. The cultivation method for promoting the growth and development of aerial roots of densely planted summer corn according to claim 1, characterized in that: In step (1), the deep tillage is performed once, and the depth of the deep tillage is 35 to 45 cm.

3. The cultivation method for promoting the growth and development of aerial roots of densely planted summer corn according to claim 1, characterized in that: In step (1), the rotary tillage is performed twice, and the depth of the rotary tillage is 15 to 20 cm.

4. The cultivation method for promoting the growth and development of aerial roots of densely planted summer corn according to claim 1, characterized in that: In step (2), the sowing method is: adopting wide and narrow row staggered planting, with a wide row of 80 cm and a narrow row of 40 cm, a planting density of 5000 to 5500 plants per mu, and a plant spacing of 20 to 22 cm.

5. The cultivation method for promoting the growth and development of aerial roots of densely planted summer corn according to claim 1, characterized in that: In step (2), the base fertilizer includes: 9.8 kg / mu of urea containing 46% N, 12 kg / mu of superphosphate containing 46% P2O5, and 11 kg / mu of potassium chloride containing 60% K2O.

6. The cultivation method for promoting the growth and development of aerial roots of densely planted summer corn according to claim 1, characterized in that: In step (3), the height of the soil is 5 cm; And / or, the method of applying water and fertilizer is: 9.8kg / mu of urea containing 46% N and 2.5kg of organic water-soluble fertilizer containing mineral potassium humate are mixed into 200kg of diluted liquid, and then applied to the soil by spraying, with 25 cubic meters of water.

7. The cultivation method for promoting the growth and development of aerial roots of densely planted summer corn according to claim 1, characterized in that: In step (4), 30 mL of 30% benzylamine·ethephon water solution is applied per mu, and 25 kg of water is added for uniform spraying.

8. The cultivation method for promoting the growth and development of aerial roots of densely planted summer corn according to claim 1, characterized in that: In step (5), the nitrogen fertilizer is applied by spraying 13.1 kg / mu of urea containing 46% nitrogen evenly on the soil, with a spraying amount of 25 to 30 cubic meters.

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